Brown-and-yellow marshbirds reduce their acceptance threshold of mimetic brood parasite eggs in the presence of non-mimetic eggs

Authors
Mermoz, Myriam Emilia; Haupt, Carolina; Fernandez, Gustavo Javier
Publication Year
2016
Language
English
Format
article
Status
Published version
Description
The recognition and subsequent rejection of brood parasite eggs is one of the most commonly observed defensive behaviors of the host. The brown-and-yellow marshbird (Pseudoleistes virescens) is a common host of the shiny cowbird (Molothrus bonariensis). This host recognizes and rejects immaculate white eggs of the cowbird, but accepts this bird’s spotted eggs. We assessed the acceptance threshold hypothesis which proposes that parasite egg recognition is context-dependent. We experimentally parasitized host nests with a spotted cowbird egg and simultaneously added: (1) one novel egg with spots similar to those of a cowbird egg but on a blue background or (2) one immaculate white cowbird egg. In this setting, 78 % of the novel blue egg with spots and 77 % of the cowbird’s immaculate white eggs were quickly recognized and rejected. The rejection frequency of spotted cowbird eggs was also high (60 %) and was not related to the type of egg which had been added to the host nest together with the spotted cowbird egg. This rejection frequency of spotted cowbird eggs is higher than the 21 % that we previously found in a similar experimental setting but in which the spotted cowbird egg was added singly to the host nest. These results support the acceptance threshold hypothesis that predicts an adaptive modulation of the antiparasite defence when the perceived risk of parasitism is high.
Fil: Mermoz, Myriam Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina
Fil: Haupt, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina
Fil: Fernandez, Gustavo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina
Subject
ACCEPTANCE THRESHOLD HYPOTHESIS
ANTIPARASITE DEFENCES
COWBIRD PARASITISM
EGG COLOUR
REJECTION BEHAVIOUR
Otras Ciencias Biológicas
Ciencias Biológicas
CIENCIAS NATURALES Y EXACTAS
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/61435